A pulsed discharge system with an intermitting partial charge for improved battery efficiency

Abstract

• A pulse discharge system comprising a partial charge phase is applied on a lead-acid battery pack • The partial charge phase can increase energy efficiency with respect to both constant and on-off discharge profiles • A maximum energetic efficiency of 89.3 % was measured, showing an improvement of ~7.3 % In this work, a lead-acid battery pack with a nominal energy of ~23.2 kWh at 1C is tested under different loading profiles, both constant and pulsed, aiming to improve the overall cycle efficiency. A partial charge phase is implemented in a pulse discharge profile, typically comprising the alternation between work and rest (idle) phases. The partial charge current, duration, and minimum/maximum cell voltage achieved during the partial phase are investigated, highlighting the effects on the overall battery performances. The investigated discharge approach can improve both energetic and faradaic efficiencies with respect to the constant current discharge up to ~10 %.